A new antibody test has been approved by the UK after an independent evaluation showed it had a high degree of accuracy and specificity.

The test, developed by Roche, is one of a number approved for use internationally.

Such tests are a key feature in many governments’ plans to relax lockdown.

But uncertainty remains over how much protection from the virus is provided by past infection.

A new test to determine if someone has been infected with coronavirus has been released onto the market.

According to its developer, Swiss pharma giant Roche, the antibody test “has a specificity greater than 99.8% and sensitivity of 100%”, pinpointing antibodies to COVID-19 present in blood samples.

Antibody tests – which check the blood for the proteins produced by our bodies’ immune systems to fight infections – have been identified by a number of countries as key to tackling the spread of the virus and loosening lockdowns, as they can show who has been exposed to the disease even if they had been asymptomatic.

After independent testing by Public Health England found the Roche test to be highly specific and accurate it became the first coronavirus antibody test approved in the UK. A second test, from Abbott Laboratories, has since also been approved in the UK. Both also have approval for use from the US Food and Drug Administration.

There are over 1,600 ongoing registered studies into the current coronavirus.

Image: Statista

How does it work?

Unlike swab tests, which indicate whether a person has coronavirus at the point they were tested, blood-based antibody tests can show whether or not someone has been infected in the past.

The Roche test and others like it rely on a machine to identify the presence of antibodies against the virus that causes COVID-19 – SARS-CoV-2 – in blood samples. It identifies antibodies from at least 14 days after infection. And the test is specific for this strain of coronavirus – so it won’t be confused by antibodies to other coronaviruses, such as the common cold.

It is a different type of test to the home finger prick blood tests which have also become available. There is still hope that such finger prick tests could help provide rapid results, but there have been some concerns over their accuracy.

What is the World Economic Forum doing about the coronavirus outbreak?

A new strain of Coronavirus, COVID 19, is spreading around the world, causing deaths and major disruption to the global economy.

Responding to this crisis requires global cooperation among governments, international organizations and the business community, which is at the centre of the World Economic Forum’s mission as the International Organization for Public-Private Cooperation.

The Forum has created the COVID Action Platform, a global platform to convene the business community for collective action, protect people’s livelihoods and facilitate business continuity, and mobilize support for the COVID-19 response. The platform is created with the support of the World Health Organization and is open to all businesses and industry groups, as well as other stakeholders, aiming to integrate and inform joint action.

As an organization, the Forum has a track record of supporting efforts to contain epidemics. In 2017, at our Annual Meeting, the Coalition for Epidemic Preparedness Innovations (CEPI) was launched – bringing together experts from government, business, health, academia and civil society to accelerate the development of vaccines. CEPI is currently supporting the race to develop a vaccine against this strand of the coronavirus.

What does a positive result mean?

Widespread use of such tests will tell governments what proportion of the population has had COVID-19, and better understand how it has spread.

But the World Health Organization has warned against using the results of diagnostic tests for “immunity passports” that would enable individuals to travel or return to work. The body is concerned about the accuracy of some tests available and points out there is still a lot of uncertainty around the degree of protection past infection gives.

People who assume they are immune to a second infection because they have received a positive test result may end up ignoring public health advice, it says.

There is also concern that such passports could lead to discrimination, creating a divide in society with, for example, employers favouring those who could prove previous infection.